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A100041
a(n) = 2*n^2 + n - 7.
13
-7, -4, 3, 14, 29, 48, 71, 98, 129, 164, 203, 246, 293, 344, 399, 458, 521, 588, 659, 734, 813, 896, 983, 1074, 1169, 1268, 1371, 1478, 1589, 1704, 1823, 1946, 2073, 2204, 2339, 2478, 2621, 2768, 2919, 3074, 3233, 3396, 3563, 3734, 3909, 4088, 4271, 4458, 4649
OFFSET
0,1
FORMULA
A100035(a(n)) = 5 for n>3.
a(n) = A014105(n) - 7 = A084849(n) - 8 = A100040(n) - 2.
From G. C. Greubel, Jul 15 2017: (Start)
G.f.: (7 - 17 x + 6 x^2)/(-1 + x)^3.
E.g.f.: (2*x^2 + 3*x - 7)*exp(x). (End)
MATHEMATICA
Table[2*n^2 + n - 7, {n, 0, 50}] (* G. C. Greubel, Jul 15 2017 *)
LinearRecurrence[{3, -3, 1}, {-7, -4, 3}, 50] (* Harvey P. Dale, Mar 25 2021 *)
PROG
(PARI) a(n)=2*n^2+n-7 \\ Charles R Greathouse IV, Jun 17 2017
CROSSREFS
KEYWORD
sign,easy
AUTHOR
Reinhard Zumkeller, Oct 31 2004
STATUS
approved